openssl/crypto/comp/c_rle.c
1998-12-21 11:00:56 +00:00

70 lines
1.1 KiB
C

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "objects.h"
#include "comp.h"
static int rle_compress_block(COMP_CTX *ctx, unsigned char *out,
unsigned int olen, unsigned char *in, unsigned int ilen);
static int rle_expand_block(COMP_CTX *ctx, unsigned char *out,
unsigned int olen, unsigned char *in, unsigned int ilen);
static COMP_METHOD rle_method={
NID_rle_compression,
LN_rle_compression,
NULL,
NULL,
rle_compress_block,
rle_expand_block,
NULL,
};
COMP_METHOD *COMP_rle()
{
return(&rle_method);
}
static int rle_compress_block(ctx,out,olen,in,ilen)
COMP_CTX *ctx;
unsigned char *out;
unsigned int olen;
unsigned char *in;
unsigned int ilen;
{
/* int i; */
if (olen < (ilen+1))
{
/* ZZZZZZZZZZZZZZZZZZZZZZ */
return(-1);
}
*(out++)=0;
memcpy(out,in,ilen);
return(ilen+1);
}
static int rle_expand_block(ctx,out,olen,in,ilen)
COMP_CTX *ctx;
unsigned char *out;
unsigned int olen;
unsigned char *in;
unsigned int ilen;
{
int i;
if (olen < (ilen-1))
{
/* ZZZZZZZZZZZZZZZZZZZZZZ */
return(-1);
}
i= *(in++);
if (i == 0)
{
memcpy(out,in,ilen-1);
}
return(ilen-1);
}